From DE 10 2004 052106 A1 and from DE 10 2004 052107 A1 latent heat storage devices for exhaust systems of combustion engines are known which operate with a phase-changing material. Such a phase-changing material is characterized in that at the respective desired storage temperature it performs a phase change between liquid phase and solid phase. When charging the latent heat storage device the phase-changing material melts and thus assumes its liquid phase. When the latent heat storage device is discharged the phase-changing material solidifies, that is it assumes its solid phase. Phase-changing materials of this type are more preferably salts.
A central problem of such latent heat storage devices is the melt expansion of the phase-changing material during the respective phase change. This expansion can amount to between 5% and 20% depending on the material. Here, every melt process results in an expansion of the phase-changing material which on solidification results in a corresponding contraction. Such material expansions can lead to extreme loading of storage device spaces filled with the phase-changing material.